A roller of the type in question is well known. It is used, for example, in connection with link chains, when the latter are employed as conveying chains.
A link chain comprises a number of chain links, in particular inner links and outer links, which are connected to one another in an articulated manner, i.e., by a chain joint. These joints allow the link chain, for example, to wrap around the chain wheels located in the drive train.
The inner links are preferably formed of two inner link plates which are connected to each other by two bushes. An inner link plate in the form of a bar link plate is also conceivable. The outer links are preferably formed of two outer link plates, which are connected to each other by two bolts. In the adjacent chain links, a bolt is in each case received in an articulated manner in the bush. Bolt and bush form the chain link. This arrangement can be repeated as desired, such that a link chain of any desired length can be produced. The number of link plates per chain link is also variable, such that it is of course also possible for more than two link plates to be provided per chain link.
In addition to numerous other applications, link chains lend themselves to be used as a conveying chain. For this purpose, rollers are in most cases mounted on extended bolts or bushes of the link chain. An arrangement on the link plates or on other components of the link chain is also conceivable. The main purpose of the rollers is that the link chain can run on a guide rail via which loads of the article to be conveyed can be carried away. The rollers also have the effect that the tensile force of the chain is reduced, since the tensile force is reduced as a result of less friction or rolling friction. Provision can also preferably be made that at least some link plates are designed to be connected to add-on parts, for example platforms. For this purpose, some chain links are equipped, for example, with an attachment mechanism for add-on parts. The attachment mechanism can be designed, for example, in the form of angled link plates which, alongside the actual link plate, have an extension arm, to which the add-on parts can be connected. This results, in cross section, in a for example L-shaped link plate.
During the conveying of various articles and raw materials, the link chains used as conveying chains are exposed to the action of the articles themselves and also to the influences of the environment and surroundings. It is possible here for dirt and other substances and liquids to penetrate into parts of the link chain, in particular the rollers, and contribute there to more rapid and increased wear.
In the field of conveyor technology on link chains, the state of the art is for rollers to be mounted on extended bolts or bushes or on other shaft elements fastened to the link chains. Such a combination of link chain and roller has been disclosed in DE 10 2006 057461 A1, for example.
If the rollers fail or reach their wear limit, it may be necessary to replace them. Since the roller and its bearing are arranged directly on the extended bolt or on a shaft element, the dismantling of the roller involves considerable effort. In such an eventuality, several component parts have to be dismantled individually in succession, including component parts that have been joined together by an interference fit. However, assembly is also laborious.